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Solid CRA vs. Clad on Carbon Steel for Piping Installation

Solid CRA vs. Clad on Carbon Steel for Piping Installation

Solid CRA vs. Clad on Carbon Steel for Piping Installation

(OP)
I am looking at replacement of about 100 feet of 16~24"Ø pipe that requires Hastelloy on the process fluid side. Current material is steel, thickness 3/8". We are still in the early design stage. I believe the thickness will be driven by the structural requirements (process pressure and temperature are fairly low). However I don't yet have information about the minimum thickness requirement. I have an aversion to fabricating from clad materials, because I have seen so many done so wrong. However I realize the choice will always be driven by cost, and that for every equipment there is a break-even point in terms of thickness.

So I have some questions:
(1) Is roll cladding still the dominant technology? What other methods are used?
(2) What is the lower practical limit for making clad steel? (Assuming 3mm (1/8") clad thickness)
(3) Are there any material integrity concerns when rolling clad plate (say, 1/2" total thickness) down to 16"Ø?

Any other advice or comments are welcomed.

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

RE: Solid CRA vs. Clad on Carbon Steel for Piping Installation

(1) Weld overlay; co-extrusion; FDIR (CermaClad); don't think anyone is still producing centrifugal cast

(2) That might be driven by pipe handling damage concerns

(3) Seam welded clad pipe is an established product with a significant number of suppliers, but you will probably not get much commercial joy out of them for 100 feet of pipe. This is definitely in weld overlay and cermaClad territory

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

RE: Solid CRA vs. Clad on Carbon Steel for Piping Installation

Explosion bonded would be my first choice. Do you want less alloy? I have seen them bonding 0.062" onto plate.
This then gets foll formed and welded.
The real issue with Clad is that you can't solution anneal the welds after forming.
With a "C" alloy I would like to see 2 hrs at 2200F after all forming and welding.

Go solid and as light as you can, even if you need stiffeners on the OD.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

RE: Solid CRA vs. Clad on Carbon Steel for Piping Installation

(OP)
metengr,
Thanks for the link. I found I had that document in my NiDI directory, and it will be a technical primary resource. I plan on giving Canadoil a call Monday.

EdStainless,
Useful information, thanks muchly. Your final suggestion has always been my preference.

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

RE: Solid CRA vs. Clad on Carbon Steel for Piping Installation

Make sure you select the thickness for the service- the 3/8" wall you have now is likely a convenience in carbon steel that comes at very low cost. If the pressure really is low, solid construction may be your best bet given the comparatively small linesize and comparatively short length. If you had a mill run of pipe to do it might be a different matter.

RE: Solid CRA vs. Clad on Carbon Steel for Piping Installation

100 feet of a single pipe run? 24 inch diameter?

Get a spray deposit machine with an automatic dispenser and linear "track" welding machine. Lay the pipe horizontally, run the spray deposit welder from one end to the other.
Rotate the pipe 3-4 inches - so a new line of pipe wall is exposed, but you have a little overlap of run1 and run2.
Run the grinder/cleaner down the next run of pipe (to remove overspary, deposits, spatter, debris, etc - then run the welder linearly again to deposit run2.
Remove welder, clean run2 to process run3.
Rotate pipe 3-4 inches again.
Repeat.

RE: Solid CRA vs. Clad on Carbon Steel for Piping Installation

For 100 feet, solid 3/16" or 1/4" wall C-276 will be more economical.

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